Memories of social experiences with other individuals can be extremely powerful, especially those produced during heightened arousal states such as reproductive encounters. The way the brain stores information about social experience, however, remains enigmatic. The broad goal of our proposal is to define the neural changes that occur during adult pheromonal imprinting, a potent form of individual recognition memory triggered by mating in rodents. We aim to establish the precise synaptic mechanisms and circuit-level effects of the chemosensory memory trace instilled by sexual experience. We first use genetic tools for fluorescently tagging the cells activated by stud pheromones during mating, allowing targeted analysis of these neurons after sensory experience with ex vivo cellular electrophysiology (Aim 1). We also develop novel approaches for visualizing how learning affects pheromone processing circuits during behavior, which should ultimately help illuminate the neural underpinnings of a much wider range of social behaviors (Aim 2). Together, this work bridges complementary cellular and network scales to provide new views of a long- standing model of chemosensory learning.